Hey all,
I've been trying to get my parameters under control, and I wonder if I've gone too far. Key point is buried below.
BASELINE:
For the past few months, I've had a cyano problem. (29 gal AGA tank, unfortunately about a 3-4" sandbed, mainly for my jawfish. 6 months old. Previously overfed. No sump; macroalgae, Caluerpa sertulariodes and prolifera, in display grew OK for a while but lighting cut downs after the cyano boom has not been good for macroalgae). This was on top of a persistent NO3 equilibrium of 20-25 and PO3 of around 0.3, despite water changes.
(calcium has been OK, in the 400ppm range, when I measured it. Alkalinity is quickly eaten up after water changes, going as low once as 140ish, which I previously attributed to the rise in NO3. Tank is about 6 months old, cycled with Dr. Tims and started adding fish once I got diatoms; now it has 2 pearly jawfish, 1 firefish, 2 growing green implosion/palythoa mutuki + one more polyp that appeared two weeks ago; an apparently growing war coral/favites pentagona on the sandbed, a reasonably growing pocillopora damicornis. Nitrification done by a, complete, marinepure block which I know is overkill but which I don't want to mess with until the system is stable. Marinepure block is loaded with small feather dusters and a growing number of encrusting purple sponges. Alk and PO3 measurements done by Hanna colorometer - this is why I'm recording alk in PPM - remainder by Salifert)
CHANGES:
I added Seachem matrix about a month ago, as well as a hob limewood airstone skimmer. The latter collects a lot of liquid. I put about 1/4 Seachem's recommended dose of purigen and phosguard about 2 weeks ago (yes I know I'm potentially adding more dissolved Al). I did two water changes in this time (60%, Omega salt two weeks ago, and 20%, last week, using RSCP). I've also been vaccuming the sandbed; I wish I could do it every day but in the end I do it maybe 2x/week.
In that time, things have gone down.
For the past 10 days or so, NO3 has dropped, consistently, down to 4-5. Since Purigen and Phosguard were added, PO3 has dropped down to about 0.18 last week and 0.10, consistently, starting Wednesday.
(Alk is still being consumed, and I dose baking soda, but its consumption rate is variable enough I'm not comfortable saying I've reached an equilibrium yet. I will go down to dosing quarter teaspoons of baking soda, every few days, with measurements to be sure it's not going bonkers. My objective number is ~165. It was 150 Wednesday, 160 Friday afternoon and 187 as of today/Saturday AM after the 0.5 tsp I added Friday night, thinking based on previous measurements it would bring alk from 160 to 170ish. I will continue to monitor alkalinity with a bias against dosing, since I'm not sure what created such large swings)
I have also started (white) vinegar dosing, 2 caps a day now.
CURRENT SITUATION:
NO3 has declined notably over the month, from ~20 to ~4-5, a number which has been consistent over the past week, using Seachem Matrix. PO3 has dropped even more dramatically, from 0.30 to 0.10, a number that has only been consistent for the past 2 days (again, I have done no water changes in a week, and the post-water change PO3 was higher). Cyano is still growing; I just dug every large mat i could find, brushed my rocks and the marinepure off again, and sucked out a good amount (but nowhere near abundant as before) detrirus. Given the water parameters, I expect the cyano to grow slower this week.
ANYWAY, TO THE KEY POINT:
I feel that this is too much change, too quickly, in NO3 and PO3. I certainly don't want to do anything more to the tank right now. I will also go on a business trip next week and won't be able to do much with the tank in the next 3 weeks.
Is this amount of change possibly negative, in that now something's out of whack and parameters might go too low in the next 3 weeks, or possibly setting me up for something unexpected in those three weeks? I know such a change is bad for the corals, but now I'm at roughly the numbers I want for the corals (yes?).
I'm trying to decide whether to:
Thoughts?
Digression: this my pre-reef tank; a system that I set up quickly to get some sort of experience, while the actual sumped reef tank's arrival has been pushed back again and again, probably won't come until the summer, since I'm balancing other things in life right now. It's my first fish tank in decades. Nevertheless, I will do things very differently, and more conventionally, next time)
I've been trying to get my parameters under control, and I wonder if I've gone too far. Key point is buried below.
BASELINE:
For the past few months, I've had a cyano problem. (29 gal AGA tank, unfortunately about a 3-4" sandbed, mainly for my jawfish. 6 months old. Previously overfed. No sump; macroalgae, Caluerpa sertulariodes and prolifera, in display grew OK for a while but lighting cut downs after the cyano boom has not been good for macroalgae). This was on top of a persistent NO3 equilibrium of 20-25 and PO3 of around 0.3, despite water changes.
(calcium has been OK, in the 400ppm range, when I measured it. Alkalinity is quickly eaten up after water changes, going as low once as 140ish, which I previously attributed to the rise in NO3. Tank is about 6 months old, cycled with Dr. Tims and started adding fish once I got diatoms; now it has 2 pearly jawfish, 1 firefish, 2 growing green implosion/palythoa mutuki + one more polyp that appeared two weeks ago; an apparently growing war coral/favites pentagona on the sandbed, a reasonably growing pocillopora damicornis. Nitrification done by a, complete, marinepure block which I know is overkill but which I don't want to mess with until the system is stable. Marinepure block is loaded with small feather dusters and a growing number of encrusting purple sponges. Alk and PO3 measurements done by Hanna colorometer - this is why I'm recording alk in PPM - remainder by Salifert)
CHANGES:
I added Seachem matrix about a month ago, as well as a hob limewood airstone skimmer. The latter collects a lot of liquid. I put about 1/4 Seachem's recommended dose of purigen and phosguard about 2 weeks ago (yes I know I'm potentially adding more dissolved Al). I did two water changes in this time (60%, Omega salt two weeks ago, and 20%, last week, using RSCP). I've also been vaccuming the sandbed; I wish I could do it every day but in the end I do it maybe 2x/week.
In that time, things have gone down.
For the past 10 days or so, NO3 has dropped, consistently, down to 4-5. Since Purigen and Phosguard were added, PO3 has dropped down to about 0.18 last week and 0.10, consistently, starting Wednesday.
(Alk is still being consumed, and I dose baking soda, but its consumption rate is variable enough I'm not comfortable saying I've reached an equilibrium yet. I will go down to dosing quarter teaspoons of baking soda, every few days, with measurements to be sure it's not going bonkers. My objective number is ~165. It was 150 Wednesday, 160 Friday afternoon and 187 as of today/Saturday AM after the 0.5 tsp I added Friday night, thinking based on previous measurements it would bring alk from 160 to 170ish. I will continue to monitor alkalinity with a bias against dosing, since I'm not sure what created such large swings)
I have also started (white) vinegar dosing, 2 caps a day now.
CURRENT SITUATION:
NO3 has declined notably over the month, from ~20 to ~4-5, a number which has been consistent over the past week, using Seachem Matrix. PO3 has dropped even more dramatically, from 0.30 to 0.10, a number that has only been consistent for the past 2 days (again, I have done no water changes in a week, and the post-water change PO3 was higher). Cyano is still growing; I just dug every large mat i could find, brushed my rocks and the marinepure off again, and sucked out a good amount (but nowhere near abundant as before) detrirus. Given the water parameters, I expect the cyano to grow slower this week.
ANYWAY, TO THE KEY POINT:
I feel that this is too much change, too quickly, in NO3 and PO3. I certainly don't want to do anything more to the tank right now. I will also go on a business trip next week and won't be able to do much with the tank in the next 3 weeks.
Is this amount of change possibly negative, in that now something's out of whack and parameters might go too low in the next 3 weeks, or possibly setting me up for something unexpected in those three weeks? I know such a change is bad for the corals, but now I'm at roughly the numbers I want for the corals (yes?).
I'm trying to decide whether to:
- do another detritus vacuuming, remove cyano, and a 20% water change Wednesday, and leave it be until I come home
- nuke it with Chemiclean tommorrow and then do a water change during the week (I have not used chemiclean yet),
- suck up some more detritus, remove cano, but not so aggressively as 1 just let it be until I come home. ( I am leaning towards this. And not just because of laziness..... )
Thoughts?
Digression: this my pre-reef tank; a system that I set up quickly to get some sort of experience, while the actual sumped reef tank's arrival has been pushed back again and again, probably won't come until the summer, since I'm balancing other things in life right now. It's my first fish tank in decades. Nevertheless, I will do things very differently, and more conventionally, next time)
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